Loss of mitochondrial membrane potential is indicative of apoptosis. ICT’s MitoPT TMRM Assay utilizes the potentiometric fluorescent dye TMRM to detect mitochondrial membrane permeability and membrane depolarization. The TMRM dye has a delocalized positive charge dispersed throughout its molecular structure. In addition, its lipophilic solubility enables it to be readily membrane permeant and penetrate living cells. The TMRM dye enters the negatively charge mitochondria where it accumulates and fluoresces orange upon excitation. When the mitochondrial membrane potential collapses in apoptotic cells, MitoPT TMRM becomes distributed throughout the cytosol. Detection of the loss of orange-red fluorescence in TMRM stained cells is a reliable method for assessing apoptosis induction or oxidative stress-induced mitochondrial depolarization in experimental cell populations.
